Finding the Fourth Proportional to 1,012.71, 1,397.61 and 570.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,012.71 : 1,397.61 = 570.60 : x
2. Step 2: Convert to fraction form
   1,012.71/1,397.61 = 570.60/x
3. Step 3: Cross multiply
   1,012.71x = 1,397.61 × 570.60
4. Step 4: Simplify right side
   1,012.71x = 797,476.27
5. Step 5: Solve for x
   x = 797,476.27/1,012.71
6. Step 6: Final answer
   x = 787.47